Some known weapon and/or firearm housings (e.g., machine guns housings) such as, the housings of the MG42/MG3, M60, NF1/AA52, FN MINIMI, PKS Kalashnikov, HK MG4, etc., are made of sheet metal stamped parts. When assembling the FN MINIMI machine gun, individual housing parts are extensively welded, which may cause distortion of the mold and/or housing parts. U.S. Pat. Nos. 5,440,099; 5,580,474; and International Patent Application No. WO 97/03785 A1 describe elaborate welding methods that attempt to minimize distortion to the mold and/or the housing when welding the individual housing parts.
Because the individual housing parts are often thin-walled stamped sheet metal parts, the parts are difficult to align and may require elaborate welding and/or stabilization. As such, the profitability of manufacturing such weapon housings may be decreased as well as the dimensional tolerances, dimensional stability, production tolerances, etc.
Other known weapon and/or firearm housings such as, housings of the MG34, the light Bren MG and the light Browning BAR MG, are made of milled parts and have a single-piece weapon housing. Housings of weapons from the 1920's and 1930's partially support and guide the breach block and, thus, require high manufacturing precision to ensure secure and/or proper functionality of the breach block.
Other known weapon and/or firearm housings such as, the housings of the N MAG from the 1950s and the Browning .50 MG from 1917, are made of riveted, prefabricated housing components. Guide rails on the MG 4, or other attachment parts may be riveted to weapon housings. While riveting is an alternative to welding, riveting is expensive and has poor tolerances.
International Patent Application No. WO 2008/147491 describes a machine gun having a housing with two perpendicular split housing halves. The housing halves, which are welded together, each include a holding fixture (e.g., ribs) for a gas rod, barrel, breech guide, reinforcement structures, etc.
DE 10 2007 011 504 A1 describes a two-part breach housing and a centering device for a breech block. The breech housing is inserted from the rear of the firearm into the weapons housing and is centered using guiding grooves. The breech housing is detachably fixed via locking means.
EP 1 357 348 B1 describes a weapon housing having two polymer housing half stocks. The half stocks are coupled together using weld(s), connection elements, grooves, a spring and/or connecting edges. For reinforcement and/or connection purposes, a polymer insert and/or strand is inserted into a recess.
WO 2008/106697 A1 describes a rifle body with a base support where two side panels or plates are detachably coupled via a snap fastener or snap lock connection. The side panels and/or attachment elements can be made of plastic. Alternatively, the side panels can be riveted to the support.